Henry Cavendish born in Nice, France in 1731 was a british physicist, a chemist, a natural philosopher and among other things one of the greatest scientific minds of the century. While he may give Sir Isaac Newton a run for his money in pure brilliance, he could completely surpass him in strangeness. He attended Dr Newcomb’s academy in England and Cambridge in 1749. He was so reserved from society that there is very little record of him, other than the odd venture into society to meet with some scientific peers.
Born into great privilege – his grandfathers were dukes – he was devoted to science, particularly the musings of the great naturalist Sir Joseph Banks. It was Cavendish’s wealth and chosen solitude that allowed him to convert his house into a laboratory and conduct a multitude of experiments undisturbed.
Cavendish was obsessed with the physical sciences (including electricity, heat, gravity and gasses to name a few), in one of his experiments he subjected himself to series of increasing electrical shocks noting the intensity of each. He was incredibly meticulous in his research, gaining great accuracy and precision in his results.
He is perhaps best known as the the first scientist to isolate hydrogen and oxygen from water. He denoted hydrogen as “inflammable air” which formed water on combustion.
If he might surpass Newton for strangeness, he blows him out of the water for shyness. Said to suffer ‘to a degree bordering disease’. At one point, when an Austrian admirer turned up unannounced at his front door Cavendish fled out of the open door and down the path, not returning for hours. Even his housekeeper only communicated with him by letter. This shyness is perhaps the reason why the name Cavendish is not a household name.
His experiments with electricity were years ahead of their time, yet remained undiscovered until the late nineteenth century when James Clerk Maxwell delved into his notes. By this period almost all of Cavendish’s discoveries had been credited to others.
Cavendish discovered or envisioned:
- Ohms law (Resistance)
- Daltons law (Partial pressures)
- Richter’s law of reciprocal proportions
- Charles law (Gasses)
- the principles of electrical conductivity
- foreshadowed the unprecedented work of Kelvin and G.H Darwin on the effect of tidal motion slowing the Earth’s rotation
- and also alluded to the group of elements now known as the noble gasses
Calculating Earth’s mass
His most famous experiment also happened to be his last. When he finally turned his attention to an old apparatus left to him by John Michell which (using lead ball-bearings, pendulums and wires) allowed for the measuring of gravitational deflection, by a larger ball-bearing on a smaller one, this would allow Cavendish to calculate the gravitational constant and the mass of the Earth.
The difference was so minute that a single breath from Cavendish would affect the result. Cavendish therefore had to record the deflection from an adjoining room with a telescope. It took almost a year for Cavendish to calculate Earth’s mass from these observations, coming to a final result of; 6 billion trillion metric tons (or 13,000,000,000,000,000,000,000 pounds). Even with todays technology, there has been no major improvement on his estimation in 1797. With today’s estimate at 5.9725 billion trillion tons.
Had Cavendish published all of his work, his influence may have been huge, and while he did not, he is still an incredibly influential scientist and set us well on our way to modern ideas and developments. Though as Harry S. Truman once said;
Its amazing what you can accomplish, if you do not care who gets the credit
And in that respect, he certainly accomplished a lot.